1 #ifndef _ASM_X86_PAGE_32_DEFS_H
2 #define _ASM_X86_PAGE_32_DEFS_H
3 
4 #include <linux/const.h>
5 
6 /*
7  * This handles the memory map.
8  *
9  * A __PAGE_OFFSET of 0xC0000000 means that the kernel has
10  * a virtual address space of one gigabyte, which limits the
11  * amount of physical memory you can use to about 950MB.
12  *
13  * If you want more physical memory than this then see the CONFIG_HIGHMEM4G
14  * and CONFIG_HIGHMEM64G options in the kernel configuration.
15  */
16 #define __PAGE_OFFSET_BASE	_AC(CONFIG_PAGE_OFFSET, UL)
17 #define __PAGE_OFFSET		__PAGE_OFFSET_BASE
18 
19 #define __START_KERNEL_map	__PAGE_OFFSET
20 
21 #define THREAD_SIZE_ORDER	1
22 #define THREAD_SIZE		(PAGE_SIZE << THREAD_SIZE_ORDER)
23 
24 #define DOUBLEFAULT_STACK 1
25 #define NMI_STACK 0
26 #define DEBUG_STACK 0
27 #define MCE_STACK 0
28 #define N_EXCEPTION_STACKS 1
29 
30 #ifdef CONFIG_X86_PAE
31 /* 44=32+12, the limit we can fit into an unsigned long pfn */
32 #define __PHYSICAL_MASK_SHIFT	44
33 #define __VIRTUAL_MASK_SHIFT	32
34 
35 #else  /* !CONFIG_X86_PAE */
36 #define __PHYSICAL_MASK_SHIFT	32
37 #define __VIRTUAL_MASK_SHIFT	32
38 #endif	/* CONFIG_X86_PAE */
39 
40 /*
41  * Kernel image size is limited to 512 MB (see in arch/x86/kernel/head_32.S)
42  */
43 #define KERNEL_IMAGE_SIZE	(512 * 1024 * 1024)
44 
45 #ifndef __ASSEMBLY__
46 
47 /*
48  * This much address space is reserved for vmalloc() and iomap()
49  * as well as fixmap mappings.
50  */
51 extern unsigned int __VMALLOC_RESERVE;
52 extern int sysctl_legacy_va_layout;
53 
54 extern void find_low_pfn_range(void);
55 extern void setup_bootmem_allocator(void);
56 
57 #endif	/* !__ASSEMBLY__ */
58 
59 #endif /* _ASM_X86_PAGE_32_DEFS_H */
60